Minimum Gear Teeth for 520 O-Ring Chain

[drivetrainUW-Platt]

I drug a past member of our formula team down to our shop to check out this years car, and he got asking questions about our chain drive. He owns a few bikes and said that all the places he has asked for front tranny gears have said that 13 tooth is the minimum the chain will safely operate on. I know a lot of ppl are always asking for 12T on here.....maybe that is why they are hard to find?????
Anyone else have any imput, I know our cars only see a few hundred miles so it might be negliable, but we have a 12 now and I'm slightly concerned

[kwancho]

Good question. I'm debating the same thing currently. It definitely depends on your chain angles, and in an attempt to shorten the packaging, I bet most of us have pretty severe angles. I did a check if we used an 11T and we would only engage 4 teeth. My question is what's the most load a single tooth can take before it breaks? If I knew what that number was, I could find the maximum load on it (if something jammed, wedging the engine in first gear at max torque) and see if the sprocket breaks.

[Big Bird]

FYI, we were using 11T front, 22T rear on our toy motor 450 - and have stripped the teeth off a number of front sprockets. If you are running low tooth numbers, make sure you keep lots of spares and replace regularly. And use a new one for the event.

Cheers,

Geoff

[BStoney]

Usually there is a group ordering a bunch of custom 12T sprockets from Sprockets Specialists. However, I understand that they may keep them in stock now...contact them for details if you want one.

www.sprocketspecialists.com (http://www.sprocketspecialists.com)

[James Waltman]

I think that a big reason you want more teeth is to avoid Chordal Action.

See Here: http://chain-guide.com/basics/2-2-1-chordal-action.html

From Here: The Complete Guide to Chain (http://chain-guide.com/toc.html)

[drivetrainUW-Platt]

so the guy did know what he was talkin about, cool...we will see how things hold up, we have a 12-45 setup right now and the gears are relatively close together

[VFR750R]

Well, we've used 11 tooth front sprockets for years, and I don't recall ever breaking one. They do wear fast however.

[MikeDutsa]

we are running a 13t front 55t rear that we got from rebel gears. it seams to do the trick, no probles yet with 24 hrs of testing on it. tbw how many testing hours is every one at if your to that stage?

[kwancho]

Originally posted by VFR750R:
Well, we've used 11 tooth front sprockets for years, and I don't recall ever breaking one. They do wear fast however.

What type of chain angles are you running? How big's an 11t sprocket?

[drivetrainUW-Platt]

Originally posted by MikeDutsa:
we are running a 13t front 55t rear that we got from rebel gears. it seams to do the trick, no probles yet with 24 hrs of testing on it. tbw how many testing hours is every one at if your to that stage?

drivetrain has 0 test time in it yet....engine is getting close to being a strong contender(still tuning), prob drive it this week.

another question, where are ppl getting half links from, apparently they used to make on with a connector link on either side, but both cycle shops I talked to said you can't get them any more, right now we have a shady tweaked 50 chain link that will prob work fine, but I would like to get the correct O ring 520 half link

[Bill Kunst]

Mike,
I thought that the chain had a o-ringed half link in it. When we shortened it (the four person 2004 team) we put a correct link in the chain. Look closely for it. The only reason that it won't be there is if someone screwed with the chain.
Bill

[drivetrainUW-Platt]

Originally posted by Bill Kunst:
Mike,
I thought that the chain had a o-ringed half link in it. When we shortened it (the four person 2004 team) we put a correct link in the chain. Look closely for it. The only reason that it won't be there is if someone screwed with the chain.
Bill
I will look, there are 2 short sections laying around as well, so it has been cut since the monster 60 tooth gear of 04. if not, where did the half link come from?

[Bill Kunst]

most chains come with one to assemble it when it is on the motorcycle. I think that is where we got ours.
Bill

[RonBurgundy01]

In Oz i know it is next to impossible to by a half link for a 520 pitch chain without actually doing as Bill said and getting the one that comes with every chain you buy. Possibly go to a bike wrecker or something and see if they'll be kind enough to give you one (obviously make sure it is in decent condition though)

Cheers

Matt

[J. Schmidt]

The concern our former member expressed wasn't about the sprocket breaking, but the chain breaking because of the stress involved with making the tight radius. He said something about an o-ring chain breaking but a x-ring chain being able to pull it off.

BTW, I found some master links here (http://www.moto-chains.com/site/898528/page/567256)

I've never heard of an x-ring chain, but that same site advertises that they are stronger while havine 50% less friction than o-ring chains, though they cost considerably more. They come in crazy colors too; I see a new part comming into play in the FSAE bling competition.

[Bill Kunst]

The only difference that I had known between oring and xring is the shape of the seal. They must use diff materials in the chain itself, or make parts stronger?!

[drivetrainUW-Platt]

joel, that link was worthless...

[J. Schmidt]

joel, that link was worthless...
Worthless? Mike, click on the "master link" link then go to the pull-down menu under ORDER INFORMATION and choose a size. The price is there too; they list a rivet-type master link for standard 520 chain at $2.25.

[drivetrainUW-Platt]

I need a HALF link not a master link, joel

[Chuck Maddocks]

aren't you guys on the same team?

[Bill Kunst]

Good call chuck. They are, and I am an alumnus. It is worth a laugh.